It's not easier to that on the ground. Those analyses are done by large radars slapped on top of satellites. They can scan huge tracts of land in very quickly with very high precision. More precise than airborne systems. They work regardless of the weather. The same satellites can keep track of river flows, forest growths, volcanic and tectonic activity, floods, structures like bridges, whole bunch of things. They can be used for extremely accurate mapping. They are insanely useful tools.